Oncology Drug Information – Iressa has a targeted mechanism of action, which results in less severe adverse reactions, side effects compared to traditional chemotherapy. Gefitinib is an oral selective epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI). The EGFR (ErbB1, HER1) receptor is similar to Her2/neu. Activation of EGFR stimulates...